A computer provided with a plurality of slots for accommodating expansion cards is known. These expansion slots are interconnected e.g. via a so-called PCI bus described in the “PCI Local Bus Specification” to which highly integrated controllers, peripheral expansion cards and/or processor and/or storage systems are also connected. The bus users can either be hard-wired to one another on a motherboard or inserted in the slots in the form of expansion cards, a combination of permanently integrated bus users and bus users in the form of expansion cards being the usual practice in computers.